The invention relates to a method for the high-speed precision clamping of a rotationally symmetrical workpiece for its outside circumference to be ground, utilising a clamping device for the axial and radial positioning of the workpiece, for clamping the workpiece in its processing position and for transferring the torque from the driving spindle head to the positioned and clamped workpiece. The invention also relates to a high-speed precision clamping device for clamping a rotationally symmetrical workpiece for its outside circumference to be ground, in accordance with the above-mentioned method. The invention thereby provides such an improvement in the clamping method and in the clamping device used therefor that a hitherto unattained accuracy is achieved for the positioning of the workpiece associated with the clamping operation and is maintained during processing of the workpiece.
Clamping methods and clamping devices for rotationally symmetrical workpieces, which have to be rotated past the tool whilst their outside circumferences are being ground, have been known for a long time. The same is also true of workpieces which are processed by grinding the outside circumference. Generally, such workpieces are clamped in a three-jaw chuck which is located on the driving spindle head and wherein the three clmaping jaws, which are directed towards the axis of rotation, radially and axially position the workpiece in a single combined positioning and clamping process and thereby clamp the workpiece so securely that the driving torque is transferred from the driving spindle to the workpiece. This known type of clamping method can keep within manufacturing tolerances which are sufficient for most of the usual manufacturing tasks. More recently, however, according to the standards set by modern techniques for grinding outside circumferences, narrower manufacturing tolerances are demanded and, consequently, the manufacturing waste--which occurs due to tolerances being exceeded--increases and makes manufacture more expensive.